#include "tomcrypt.h"
#if defined(LTC_BASE64) || defined (LTC_BASE64_URL)
#if defined(LTC_BASE64)
static const char * const codes_base64 =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
#endif
#if defined(LTC_BASE64_URL)
static const char * const codes_base64url =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
#endif
static int _base64_encode_internal(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen,
const char *codes, int pad)
{
unsigned long i, len2, leven;
unsigned char *p;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(out != NULL);
LTC_ARGCHK(outlen != NULL);
len2 = 4 * ((inlen + 2) / 3);
if (*outlen < len2 + 1) {
*outlen = len2 + 1;
return CRYPT_BUFFER_OVERFLOW;
}
p = out;
leven = 3*(inlen / 3);
for (i = 0; i < leven; i += 3) {
*p++ = codes[(in[0] >> 2) & 0x3F];
*p++ = codes[(((in[0] & 3) << 4) + (in[1] >> 4)) & 0x3F];
*p++ = codes[(((in[1] & 0xf) << 2) + (in[2] >> 6)) & 0x3F];
*p++ = codes[in[2] & 0x3F];
in += 3;
}
if (i < inlen) {
unsigned a = in[0];
unsigned b = (i+1 < inlen) ? in[1] : 0;
*p++ = codes[(a >> 2) & 0x3F];
*p++ = codes[(((a & 3) << 4) + (b >> 4)) & 0x3F];
if (pad) {
*p++ = (i+1 < inlen) ? codes[(((b & 0xf) << 2)) & 0x3F] : '=';
*p++ = '=';
}
else {
if (i+1 < inlen) *p++ = codes[(((b & 0xf) << 2)) & 0x3F];
}
}
*p = '\0';
*outlen = (unsigned long)(p - out);
return CRYPT_OK;
}
#if defined(LTC_BASE64)
int base64_encode(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen)
{
return _base64_encode_internal(in, inlen, out, outlen, codes_base64, 1);
}
#endif
#if defined(LTC_BASE64_URL)
int base64url_encode(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen)
{
return _base64_encode_internal(in, inlen, out, outlen, codes_base64url, 0);
}
int base64url_strict_encode(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen)
{
return _base64_encode_internal(in, inlen, out, outlen, codes_base64url, 1);
}
#endif
#endif